Double Hem Sheet Metal

Hemming and seaming are two similar metalworking processes in which a sheet metal edge is rolled over onto itself.

Double hem sheet metal.

In sheet metal hems are used to create folds in sheet metal in order to stiffen edges and create an edge safe to touch. And while hems or seams reinforce a sheet metal edge their main purpose is to improve appearance by hiding burrs and rough edges on metal back splashes and other sheet metal installations. It s not that a pittsburgh or double lap seams didn t work. The double fold hem is the most basic hem out there which also makes it one of the most useful hems you can learn.

In car part production hemming is used in assembly as a secondary operation after deep drawing trimming and flanging operations to join two sheet metal parts outer and inner together. Determining flat patterns of hems. The flat pattern of a hem is not calculated in the same fashion as a typical bend. Hemming is a metalworking process where a sheet metal edge is mechanically bent to fit an uneven surface or simply roll over onto itself.

A hem provides stiffness to a design or provides a smooth rounded external edge on a part to eliminate sharp edges. Let s begin by looking at the hem. Sheet metal hem features are typically added to provide one or more thicknesses of material along an edge of a face or flange. You can create single double rolled and teardrop hems.

In sheet metal hemming means to fold the metal back on itself. While those in the sheet metal trade form dozens of different kinds of hems and seams most are simply outdated and only three are in general use. Hemming is nothing but to fold the metal back on itself. As the name indicates a double fold hem is made when you fold the fabric over on itself to the wrong side two times to hide the raw edges and create a neat finished hemline.

Typical parts for this type of assembly are hoods doors trunk lids and fenders. A wire edge fig. Hemming is the process in which the edge is rolled flush to itself while a seam joins the edges of two materials. 2 56 is often specified in the plans objects such as ice cube trays funnels garbage pails and other articles formed from sheet metal are fabricated with wire edges to strengthen and stiffen the jobs and to eliminate sharp edges the.

Hems are commonly used to reinforce an edge hide burrs and rough edges and improve appearance.